Arrangement for plants for paint spraying of continuously moving objects



N. DOCK ETAL ARRANGEMENT FOR PLANTS FOR PAINT SPRAYING Feb. 2, 1965 OF CONTINUOUSLY MOVING OBJECTS Filed Feb. 21, 1962 INVENTORS.

,NILS DOCK AKE ARBORGH GUNNAR WILHELMSSON} ATTYS.

United States Patent 3,168,029 ARRANGEMENT FUR PLANTS FOR PAENT SPRAY- ING 6F CGNTTNUDUSLY MQVING GBEECTS Nils Dock, Saltsje-Euvnas, Aka Arhorgh, .Tonhoping, and

Gunnar Wiihelrnsson, Smalands Taberg, Sweden, as-

signors to Airtiebolaget Svenska Fiaktfabrilren, Stochhelm, Sweden Filed Feb. 21, 1%2, Ser. No. 174,835 2 Claims. (61. 98-115) The present invention relates to paint spraying apparatus of the same general type as that shown in US. Patent No. 3,138,087 for paint spraying of continuously or intermittently forwarded objects and which are particularly intended for Wide boothsis characterized in that the bottom of the booth is formed by two or more V-shaped longitudinal channels, each terminating in a longitudinal slot for discharging the ventilating air to a drop separator, and that this consists of a chamber below the booth of the same width as the booth together with vertical exhaust shafts for the discharged ventilating air situated on each side of the booth, each shaft being provided with a number of inclined baffles, which are designed to repeatedly deflect the air and thus produce additional precipitation of the entrained drops of paint and liquid. According to a suitable embodiment of the invention, means for supplying additional washing liquid are provided in the lower part of the vertical shafts for final purification of the discharged ventilating air.

The invention will now be described more in detail with reference to the accompanying drawing which shows a cross section through an exemplified embodiment of a plant constructed according to the invention.

In the drawing 1 designates a closed elongated wide spray booth, through which the objects 2 to be sprayed with paint are conveyed. Heated and possibly filtered ventilating air is supplied through a conduit or duct 3 from means not shown in the drawing. The ventilating air is uniformly distributed across the complete horizontal cross section of the booth by means of air filters 4 incorporated in the booth roof. In the case shown the booth has a bottom made with two longitudinal V-shaped bottom channels, 5a and 5b, each provided with a longitudinal slot, 6a and 6b respectively. Through the said slots, ventilating air is conducted to a drop separator, consisting of a duct 7 arranged below the bottom of booth 1 and with the same width as the booth together with vertical exhaust shafts, 8a and 8b, for the discharged ventilating air situated on each side of the booth. The slots 6a, 6b, as shown, are narrow and on the sides have inwardly projecting flanges which direct the paint and water inwardly into the slots where the downflowing air breaks up much of the water into fine particles and carries it off into the shafts 8a, 8b to assist in washing out and 3,l68,h2 Patented Feb. 2, 1965 precipitating any paint particles which tend to escape into the shafts. The flanged slots 6a, 6b are of the same type as the flanged slot shown in the patent referred to above. 9a and 9b designate a number of inclined baflles, designed to repeatedly deflect the air and thereby produce additional precipitation of the entrained drops of paint and liquid. 10, 11 and 12 designate means for supplying washing liquid. Means 10 and 12 could suitably be made to supply additional washing liquid into the lower part of the vertical shafts.

What we claim is:

1. Paint spraying apparatus for moving objects, comprising in combination, an enclosed elongated wide spray booth through which objects to be sprayed travel, means for supplying ventilating air through air inlets arranged at the top and along the length of the booth, a liquid catch basin in the bottom of said booth, means defining a full length longitudinal drop separator duct in said booth below the level of travel of articles through the booth and above the liquid level in said basin, a bottom wall for said duct having a bottom outlet to said basin closed to the passage of air therethrough and the bottom wall sloping toward said outlet, a top wall for said duct having at least one V-shaped full-length longitudinal channel converging to a narrow outlet slot with inwardly projecting flanges through which liquid and air flow, said top wall extending completely across the bottom of said booth, means for supplying washing liquid above said top wall on both sides of said channel to flow down with the paint particles and air through said narrow slot, said duct having an air outlet on each side, a bafiled exhaust shaft leading from each of said side outlets, and means to supply additional washing liquid to the upflowing air and entrained paint and washing liquid particles in said exhaust shafts, said bottom wall of the duct being of a width to embrace the width of said spray booth and said exhaust shafts.

2. Apparatus as set forth in claim 1, in which said construction is symmetrical about a central longitudinal Vertical plane with a V-shaped longitudinal channel with a narrow slot in the bottom on each side of the central plane, and a baflle for the duct outlet on each side.

References Cited by the Examiner UNITED STATES PATENTS 2,086,514 7/37 Saunders 98-115 2,230,646 2/41 Klausmeyer 98-115 FOREIGN PATENTS 871,355 6/61 Great Britain.

ROBERT A. OLEARY, Primary Examiner.

CHARLES E. OCONNELL, Examiner. 

1. PAINT SPRAYING APPARATUS FOR MOVING OBJECTS, COMPRISING IN COMBINATION, AN ENCLOSED ELONGATED WIDE SPRAY BOTH THROUGH WHICH OBJECTS TO BE SPRAYED TRAVEL, MEANS FOR SUPPLYING VENTILATING AIR THROUGH AIR INLETS ARRANGEDC AT THE TOP AND ALONG THE LENGTH OF THE BOOTH, A LIQUID CATCH BASIN IN THE BOTTOM OF SAID BOOTH, MEANS DEFINING A FULL LENGTH LONGITUDINAL DROP SEPARATOR DUCT IN SAID BOOTH BELOW THE LEVEL OF TRAVEL OF ARTICLES THROUGH THE BOOTH AND ABOVE THE LIQUID LEVEL IN SAID BASIN, A BOTTOM WALL FOR SAID DUCT HAVING A BOTTOM OUTLET TO SAID BASIN CLOSED TO THE PASSAGE OF AIR THERETHROUGH AND THE BOTTOM WALL SLOPING TOWARD SAID OUTLET, A TOP WALL FOR SAID DUCT HAVING AT LEAST ONE V-SHAPED FULL-LENGTH LONGITUDINAL CHANNEL CONVERGING TO A NARROW OUTLET SLOT WITH INWARDLY PROJECTING FLANGES THROUGH WHICH LIQUID AND AIR FLOW, SAID TOP WALL EXTENDING COMPLETELY ACROSS THE BOTTOM OF SAID BOOTH, MEANS FOR SUPPLYING WASHING LIQUID ABOVE SAID TOP WALL ON BOTH SIDES OF SAID CHANNEL TO FLOW DOWN WITH THE PAINT PARTICLES AND AIR THROUGH SAID NARROW SLOT, SAID DUCT HAVING AN AIR OUTLET ON EACH SIDE, A BAFFLED EXHAUST SHAFT LEADING FROM EACH OF SAID SIDE OUTLETS, AND MEANS TO SUPPLY ADDITIONAL WASHING LIQUID TO THE UPFLOWING AIR AND ENTRAINED PAINT AND WASHING LIQUID PARTICLES IN SAID EXHAUST SHAFTS, SAID BOTTOM WALL OF THE DUCT BEING OF A WIDTH TO EMBRACE THE WIDTH OF SAID SPRAY BOOTH AND SAID EXHAUST SHAFTS. 